Author Topic: 8bit raw?  (Read 3787 times)

Teamsleepkid

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8bit raw?
« on: January 05, 2017, 09:53:48 PM »
Is there such a thing as 8 bit raw? I like 10 bit the most so far because of the resolution gain. Just wondering if 8 bit could get us even more resolution and dynamic range than h.264? Or would it basically be the same thing as h.264?
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dfort

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Re: 8bit raw?
« Reply #1 on: January 05, 2017, 10:50:29 PM »
Did you post this to Duplicate Questions or did a moderator move it?

I wonder about that too. 8-bit uncompressed is pretty good and doesn't have the artifacts of H.264.
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Teamsleepkid

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Re: 8bit raw?
« Reply #2 on: January 05, 2017, 11:16:40 PM »
I think it got moved. Maybe it's been asked before? I've never seen it on here. I started to ask about it in the mv1080 topic but that was off subject so I did this post..
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a1ex

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Re: 8bit raw?
« Reply #3 on: January 06, 2017, 12:28:11 AM »
8-bit linear data doesn't make much sense; maybe only at very high ISO. 10-bit linear is already showing its limits. See also a 8-bit DNG created in post here.

On the other hand, 10-bit raw (Bayer) data with a nonlinear curve applied would be nearly lossless on current sensors, and 8-bit nonlinear would be very close.

The only issue: how to configure Canon's image processing modules to do this stuff?

BTW, recovering the scene-linear data from a clean HDMI recording (or even from a JPG or H.264) could be interesting (one just has to undo Canon's color science). It's already done, at least to some extent (lookup e.g. radiometric calibration).

Teamsleepkid

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Re: 8bit raw?
« Reply #4 on: January 06, 2017, 08:57:29 AM »
I got a feeling it might be kinda cool.. I saw a build before that had 10,11,12,13 and 14 bit. I'd love to see one that said 8,10,12,14. If it's possible.. I was thinking if the dynamic range is still good and the sharpness is good I might just through it into black and white if the color isn't so great or there's a lot of noise.
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dmilligan

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Re: 8bit raw?
« Reply #5 on: January 06, 2017, 06:17:01 PM »
11 and 13 were never possible. They were in the menu list because of my laziness and a quirk of the menu API. You couldn't actually select or use them. It's very easy to add 8 to the list, making it actually work is another story, its not clear what one would pass to the current method to indicate 8 bit or even if that's possible (currently 10bit is selected with 0). There may be some separate module, idk.

I do suppose getting the hardware to give us 8 bit would be very useful for in camera preview and analysis (histogram and other raw overlays).

Teamsleepkid

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Re: 8bit raw?
« Reply #6 on: January 06, 2017, 06:34:40 PM »
Oh ok. That's a pretty good explanation. What's less than zero? Lol
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